The cosmetic appearance of teeth is of great importance to many individuals. These individuals typically desire a “bright” smile and white teeth. Unfortunately, the surface color of teeth generally dulls and discolors over time due to the absorbent nature of dental material.
Tooth coloration is influenced by a combination of intrinsic, such as age and genetics, and extrinsic factors, such as staining caused by various foods, beverages, medications, and tobacco use. Even with regular brushing and flossing, exposure to staining and discoloring substances over many years can cause noticeable discoloration. As such, there is a need for products and processes to quickly and safely whiten teeth.
One solution to the problem of tooth discoloration is the application of veneer facings made of porcelain, composites or ceramic. However, the application of veneer facings is expensive and requires the assistance of trained dental professional.
Bleaching agents may also be used to whiten teeth. The application of the bleaching agent may also require the assistance of a dental professional (i.e., application of concentrated oxidizing agents) and/or multiple applications and may not achieve the desired degree of whitening. Over-the-counter bleaching products typically use lower concentrations of the bleaching agent(s) and often require repeated application of the product. However, the use of bleaching agents has been associated with several undesirable side effects including chemical burns, irritation to the gums, and an increase in tooth sensitivity.
White colorants may also be used to whiten teeth. The non-toxic colorants are typically white pigments or a combination of white pigments with other non-white pigments to achieve a more “natural” white appearance. However, the use of pigments to improve the cosmetic appearance of teeth generally lacks the required durability to achieve the desired cosmetic effect.
There have been various attempts to enhance the binding durability of tooth whitening agents. U.S. Patent Application Publication No. 2005-0069501 to Ibrahim et al. describes the use of a siloxane adhesive and a whitening particulate (hydroxyapatite powder) as a tooth whitening composition. PCT publication WO2006/068011 by Shimako et al. discloses a tooth whitening composition comprising (A) one or more pigments, (B) pullulan, and (C) one or more members selected from lysozyme, cationized cellulose and poly lysine, wherein the components (B) and (C) are used to attach the metal oxide powder on the tooth surface. Neither reference discloses a tooth whitening system comprising a peptide-based reagent suitable for enhancing the durability of a polymer-coated white colorant.
Short peptides having strong affinity for various body surfaces have been identified using a biopanning technique, such as phage display (U.S. Pat. Nos. 7,220,405; 7,309,482; and 7,285,264; U.S. Patent Application Publication Nos. 2005-0226839; 2007-0196305; 2006-0199206; 2007-0065387; 2008-0107614; 2007-0110686; and 2006-0073111; and published PCT applications WO2008/054746; WO2004/048399, and WO2008/073368). However, peptide-based reagents comprising at least one portion having affinity for a tooth surface and at least one portion having affinity for a polymer-coated whitening agent are not described.
U.S. Patent Application Publication No. 2007/0065387 to Beck et al. describes the use of peptide-based reagent comprising at least one portion having strong affinity for hair or skin and at least one portion having affinity for a polymer-coated colorant. Oral care compositions comprising a peptide-based reagent and at least one polymer-coated white colorant are not provided. No tooth-binding peptides or cellulose acetate-binding peptides are described.
The problem to be solved is to provide compositions and methods for delivery of a polymer-coated white colorant to a tooth surface for whitening teeth.